There is possibility that u might have psychosomatic disorder
,Where ur day to day life exaution creates some kind of tension in mind...changes ur brain chemisttry and pain perception....so u constantly have moving kind of pain which cannot be explained by any physical illness or on investigation.And doesnt respond to common pain killer and no relief even on rest which happen in physical disorder.
So if u have been thoroughly investigated and Dr. found nothing abnormal still suffering alot and disturbing ur routine then pls. consult a Psychiatrist
he will guide u and if possible will help to get rid of this problem.